SAN DIEGO--
Ligand Pharmaceuticals Incorporated (NASDAQ:LGND) today announced
the initiation of a Phase I clinical trial with LGD-4033, a
next-generation selective androgen receptor modulator (SARM) designed to
provide the benefits of androgen receptor stimulation on skeletal muscle
and bone without the side effects of currently marketed androgens. The
Phase I study will evaluate the safety, tolerability and pharmacokinetic
profile of orally administered LGD-4033.

-- LGD-4033 is highly selective for the androgen receptor.
-- Gene transcriptional regulation assays using muscle or bone cells
demonstrate that LGD-4033 is a potent, full agonist producing efficacy
comparable to the natural steroidal androgen dihydrotestosterone.
-- In repeat oral dosing studies LGD-4033 increases skeletal muscle mass.
-- In the ovariectomized rat model of post-menopausal osteoporosis,
LGD-4033 had anabolic activity in cortical bone, significantly
increasing cortical bone formation rates, bone strength and bone
density. LGD-4033 also suppressed bone turnover at cancellous bone
sites, leading to an increase in lumbar spine bone density and strength.
-- In repeat oral dosing studies, LGD-4033 is a weak partial agonist on the
prostate gland with more than 500-fold selectivity for muscle versus
prostate. This indicates an absence of the prostatic hypertrophy that
occurs with the currently marked androgens.

"LGD-4033 has shown an excellent SARM profile to date in terms of
efficacy, potency and selectivity, and it is potentially a novel
therapeutic for muscle and bone-related disorders such as cachexia and
frailty," said John L. Higgins, President and Chief Executive Officer of
Ligand Pharmaceuticals. "This program is another example of how the
success of Ligand's research platform, which so far includes five
approved drugs, allows us to continue investing in and strengthening a
portfolio of promising candidates to address major clinical needs and
commercial market opportunities."

SARM Program

SARMs are designed to elicit the desired biological effects without the
undesirable side effects or potential risks over time of currently
marketed androgens, providing a wide range of opportunities for the
treatment of many diseases and disorders in both men and women.
Tissue-selective androgen receptor agonists may provide utility in the
treatment of a number of medical conditions, including frailty,
cachexia, osteoporosis, sexual dysfunction and hypogonadism. Ligand has
discovered orally active, non-steroidal SARM compounds, such as LGD-4033
and LGD-3303, based on tissue-specific gene expression and other
functional, cell-based technologies.

About Ligand Pharmaceuticals

Ligand discovers and develops new drugs that address critical unmet
medical needs of patients with muscle wasting, frailty, hormone-related
diseases, osteoporosis, inflammatory diseases, anemia, asthma,
rheumatoid arthritis and psoriasis. Ligand's proprietary drug discovery
and development programs are based on advanced cell-based assays,
gene-expression tools, ultra-high throughput screening and one of the
world's largest combinatorial chemical libraries. Ligand has strategic
alliances with major pharmaceutical and biotechnology companies,
including Bristol-Myers Squibb, Celgene, Cephalon, GlaxoSmithKline,
Schering-Plough, Pfizer and Wyeth Pharmaceuticals. With nine
pharmaceutical deals and more than twenty different molecules in various
stages of development, Ligand utilizes proprietary technologies for
identifying drugs with novel receptor and enzyme drug targets.

Caution Regarding Forward-Looking Statements

This news release contains forward-looking statements by Ligand that
involve risks and uncertainties and reflect Ligand's judgment as of the
date of this release. These statements include those related to clinical
trials of LGD-4033, other SARM related drugs, market size and potential,
LGD-4033's profile, efficacy, potency, selectivity, and competitiveness,
and the strength of Ligand's product portfolio. Actual events or results
may differ from our expectations. For example, there can be no assurance
that LGD-4033 or other potential drugs will progress through clinical
development or receive required regulatory approvals within the expected
time lines or at all, that clinical trials will confirm any
characteristics or profile presented here, that there will be a market
of any size for LGD-4033, or that LGD-4033 or any drugs will be
beneficial to patients or successfully marketed. Additional information
concerning these and other risk factors affecting Ligand can be found in
prior press releases as well as in public periodic filings with the
Securities and Exchange Commission, available via www.ligand.com.
Ligand disclaims any intent or obligation to update these
forward-looking statements beyond the date of this release. This caution
is made under the safe harbor provisions of the Private Securities
Litigation Reform Act of 1995.